GeoServer 1.7.1 Released

The biggest improvement in this release is better Google Earth support. Using revamped KML output (known as the KML “reflector”) GeoServer can now output vector super-overlays. Prior to this version, data served by GeoServer when viewed in Google Earth would only update when the the camera stopped. With super-overlays, however, views are updated dynamically. Data is also broken up into regions which are used to sort features into a hierarchy so that more prominent features are visible at higher zoom levels and less prominent features become visible at lower zoom levels. Super-overlays also work on raster datasets, providing lower resolutions versions of imagery (overviews) at higher zoom levels and higher resolutions at lower zoom levels.

All of this is is a huge step for GeoServer, as it is now the first major GIS server to return placemarks, lines, and polygons with the super-overlay mechanism. This means that serving data through Google Earth is a more seamless experience; your data will look like it is naturally part of Google Earth. And with super-overlays, you can serve large amounts of data with minimal performance issues.

In addition to super-overlays, GeoServer now has support for adding a height attribute to features (also known as “extrudes”), which allows Google Earth to render data in 3-D. Height information is specified via a template, similar to how one specifies time attributes to create animations. We have a nice tutorial on how to use the height feature with super-overlays, to see this in action, but here’s a quick screenshot.

Although the default mode of output using the improved KML reflector is now the super-overlay mode, the previous default, refresh mode, is still available. Also available is a download mode which outputs a self-contained KML file, useful for situations where server access is not necessary or possible.

Special thanks go out to David Winslow for all the great work implementing all the new KML functionality.

This version has more than just improved Google Earth support. GeoServer now has an official SQL Server extension (described previously). In addition, there is a new and improved Oracle extension which provides better performance and security from the previous version.

Further improving the visualization experience is GeoWebCache, a WMS tile-caching program. Previously available as an extension (and still available as a standalone product), GeoWebCache is now built-in to GeoServer and can vastly accelerate map rendering. We will be talking more about GeoWebCache in a future post.

As always with any GeoServer release a heap of other improvements and bug fixes are included. A total of 98 issues were handled for this release.

We’re very excited about this release, and we encourage you to download, try it out, and let us know what you think. Comments and feedback are always welcome on the mailing list, as the community is always interested to hear how people are using GeoServer. Stay tuned for the 1.7.2 release, slated for release in the next month or so, which will include new breakthroughs in support for GeoSearch.